Plush valve



H. F. HUDSON June 2,

FLUsH'vALvE Filed July 28, 1923 2 Sheets-Sheet 2 Patented .lune i?,

HAVRD F. HUDSON, 0F WICHITA, KANSAS. 'v

Application lcd July 2B,-

To aZZ whom, t lmay concern.'

Be it known that I, HAvAnD F. IIposoN, citizen ofthe United States,residing at lVichita, county of Sedgwick, and State of Kansas, haveinvented certain new and, useful Improvements in Flush Valves; and I dodeclare the following to be a full,'clear, and exact description of theinvention, such as will enable othersskilled in the art to whichitappertains to make and use the same, reference being had to theaccompanying drawings, and to the characters of reference markedthereon, which form a part of this specification.

This invention relates to improvements in flush valves of the typeemployed in connection with toilet fixtures and sometimes referred to asfiushometers7 It is well known that the ordinary flushing'apparatusemployed in connection with toilet fixtures are unsightly and are oftenunsatisfactory intheir operation. In order to enable the tank and alliedfloat-operated valve to be dispensed with, it has been proposed that thesame shall be replaced by a valve mechanism that will permit a prede'termined amount of' water to flow, which can be controlled by a pilotvalve and which will automatically clse.

It is the object of this invention to produce a flushometer that shallbe of simple and substantial construction, of neat and pleasingappearance, and which shall be so constructed and designed that it willbe positive and reliable in its operation.

The above and other objects which will appear as the descriptionproceeds, are attained by mea-ns of a construction which I will nowdescribe in detail, reference for this purpose being had to theaccompanying drawing in which the preferred embodiment of my inventionis shown, and in which:

Fig. 1 shows a side elevation of a toilet fixture which is equipped withmy improved fiush valve.`

Fig.- 2 is a vertical section through the valve and shows therelationship oi lthe parts.

Fig. 3 .is a transverse section taken on line 3-3, Fig. 2.

Fig. l is a detail showing a modified 'form of construction.

Fig.' 5 is a section taken on Fig. 4,

FLUSH VALVE.

1923. Serial No. 654,346.

Fig. 6 is a -side elevation showing the appear-ance of my modified formof construction.`

showing a booster that is occasionally required to be embodied in thecombination.

Fig. 8 is a ver tical section through a house showing the relationshipof the various e1ements ofv my combination. l

Fig. 9 is a side elevation of my improved pressure booster tank withportions thereof broken away.

Fig. 10 is a section taken on line 'lO- 10. Fig. 9.

Fig. 11 is a modified form of pressure tank wherein the air is containedin an airtight. bag, and this view is shown partly in section.

Fig. 12 shows a diametrical section of a modified form of pressure tank;and Fig. 13 is a section similar to that shown in Fig. 13 butv differstherefrom by having a flexible metal diaphragm.

The same reference characters will be em Fig. 7 is a longitudinalsectional detail l ployed to designate the same parts through out theseveral views.

Numeral 1 represents the floor and 2 the wall of a toilet or bathroom. Abowl 3 rests 'upon the floor l and is connected to the lumbing in theusual manner. A pipe 4, wiich is preferably one inch or larger, connectsdirectly to the water supply. The flow of water throu h the pipe 4: iscontrolled by means o? my improved valve which I will now proceed todescribe:

My valve consists of a body member 5, made somewhat in the shape of a T.The laterally projecting portion 6 is internally threaded and isdesigned to connect to the bowl in the manner shown in Fig. 1. The upperend 7 is externally vthreaded and adapted to receive a cap 8 of a unionby means of which the body member 5 is connected to the lower end ofpipe 4. The lower end 9 of the member 5 is externally threaded and hasattached thereto a cylinder 10 within which is recipi'ocably mounted apiston 11. A .piston rod 12 is connected to the piston and has securedto the end thereoi a rubber or metal ball 13 which engages the inclinedsides 14 vof the opening 15. When the piston 11 and the valve member loa13 are in vtheir lower position, as shown in i from pipe 4 so tha-t lnowatercan flow out therefrom, similar. to an ordinary check valve. Ifsutiicient pressurev is ap lied to the bottom 'of the piston 11 to forcetie valve member 13 from its seat, water will flow into the interiorof'member' 5, through the projecting portion 6,* through the pi e 4, andinto the bowl 3. Secured to the ower end of the cylinder is a cap 16provided with a central tubular. member 17 which terminates in athreaded portion 18. A pipe 19 extends from the threaded end 18.to thevalve 20, wherever it may be located for the convenience of the user,and is secured to the end 18 by means of a cap 21. The valve casing 20has a central opening 22 with which the pipe 19 connects. -The opening22 connects with the enlarged portion 23, the inclined conical Walls 24forming a valve seat for cooperating with the valve 25, Which. issecured to the inner end of the valve stem 26. The stem 26l extends outthrough the gland 27 and terminates in ,a head 28. A spring 29 surroundsthe stem and abuts its ends against the head 28 and the cap 30 and tendsto hold the valve member against the valve seat 24. A pipe 31 extendsfrom the supply pipe 4 to the pilot valve 20 and has its upper endconnected to pipe 4 by means of suitablecouplings such as shown in- Fig.2 or by other suitable means, and a, tine screen 19A, as drawn, isinserted therein to keep dirt out of the top of the valve. If pressureis exerted on the handle 28, sufiicient to move the valve member 25 fromthe seat 24 it is apparent that water will flow through pipes 31 and 19into the bottom of the cylinder between the ca 16 and the piston 11.Since the area o the piston is greater than the cross-sectional area 'ofthe valve member 13, it is evident that a greater force will be producedtending to move the valve to open position than is ex'- erted in theopposite direction, and the valve will therefore open and permit waterfrom the pipe 4 to ow into the interior of mem-l ber 5^. When the valve25 is closed, the water 'within the cylinder will bec'ome trapped, so tospeak, and would maintain the valve 13 in open. position indefinitely,which, of course, would not be desirable. I have therefore rovided thecylinder with a channel 32 whic 1 extendsA practically the entire lengththereof betweenv the. 'threaded portion at' each end. vThe 4trappedwater which was em loyed-.for thepurpose of opening the va ve can escapethrough -the channel 32, thus allowing `the valve to close. By properlyprop'ortioning the size or cross? sectional area of the groove 32, thevalve 13 can be made to remain open a sulicient length of the time toeffect the necessary ilus ing of the bowl. The amount of Water requiredto properl flush a bowl depends on several varying. actors and thelength of pacity of the bowl.

time the water must flow is also different for different installations,depending, among other thin s, on the pressure of the water supply anthe style and water-carrying ea- I have therefore found that I mustprovide means whereby the rate at which the valve closes can be adjustedto suit the' conditions under which the valve operates. I make thecross-section of the groove 32 suflicientl `large to permit the valve toclose in t e -minimum time required. Where it is desirable to make thevalve close more slowly, I employ an adjusting means comprising a screw33 whose end projects into the groove 32. A projectingth'readed lugl 34vis provided on the cylinder and threadedly connected to this is a cap 35which forms with the end of the lug a chamber for the reception ofpacking material 36. When the effective cross-section of the grooveis tobe decreased in order to slow down the motion of the'piston, the screw33 is turned so that the end thereof projects into the groove thusreducing the area of the opening through which the water must flow. v

The movement of the cylinder surface past the screw 33 tends tofacilitate the removal 'of any dirt that collects at this point andkeeps the passage open and in operative condition. The force which tendsto close the valve 13 is the resultant of three diii'erent forcesproduced as follows: First, the pressure of the water in pipe 4 and itsfriction against the valve member 13 produces a force which tends toclose the valve; second, the reaction of the water from the valve 13against the upper surface of the piston, this last .forcebeingconsiderable, as the water must change its direction degrees or more;and, third, the weight of the piston pulls valve 13 into a closedposition on the principle of a check-valve. The operation of the valvemechanism described above is as follows:

Y The pipe 4 is connected to the supply which must be ample to cause agood flow of water through this pipe.v This pipe must be one inch orlarger. With valves 13 and 20 in closed position, no Water -will flowfrom pipe 4 and valve 13 will remain firmly scated against lthe valveseat due to the force produced bythe Water which -is equal to the.pressure times the area of the valve member at the point 4where itcontacts with the seat. I will call attention at. this. point .to thefact that the valve seat 14 and the valve member 13 contact alongsurfaces which are inclined to the axis of the valve. Thepressure perendicular to the. contacting surfaces is t erefore greater than theforce in the direction of the axis and varies inversely as the sine ofthe angle which' the surfaces in contact make with the axis, thuscreating a positive closing contact pressure position shown in Figi 2and that pressureis exerted von the head 28 sutlicient to open the same.Water will then tiow through the pipe 31, through valve 25, through pipe19 and into the space between the cap 16 and the head of the piston 11and move the latter upwardly, thereby openin the valve 13. After valve13 has been ful yopened, the valve 25 is closed. The water in thecylinder below the lower surface of the piston willl now have no otherway of escape than through the roove 32 and the valve 13 will close,butv on y as fast as the escape of water through the channel 32 permitsand this can be regulated by means of the screw As the valve closesgradually and in accordance with the rate at which the water can escapethrough the channel 32, there will be no tendency for the piston andvalve to hammer and the valve will operate quickly andsilently.

I t is apparent that the valve need not be directly attached to thetoilet bowl or located 1n the positionshown vin Fig. 1, but that it canbe located at any reasonable distance therefrom and the ischarge port 6connected to the fixture by means of a pipe 4. The valve can thereforebe located at any convenient place in the wall, floor or in the basementof the house and pipes 19 and 31 extended to the pilot valve 20 whichmust be located within convenient reach of the toilet fixture.

In Figs. 1 and 7 I have shown an element indicated bythe numeral 37,which I term a pressure booster.. This pressure booster is merely anenlarged portion of pipe 4 and may be formed integrally therewith asshown in Fig. 7, or separately and connected to'ltwo adjacent ends ofthe pipe. The

' water enters the pressure booster in the direction of the arrow 38 andthe lower end of the upper section of pipe ltprojects into the pressure`booster chamber inthe manner indicated at 39 in Fig. 7. The pipe 31 isconnected to the side of the pressure booster chamber in the mannershown in Fig. 7. The purpose of the pressure booster is to increase thepressure of the water at the point where the pipe 31 is connected, sothat the pressure on the head of the piston will be greater than itotherwise would be when the water in pipe 4 is flowing.

The pressure booster operates o'n the same principle as a Venturi meter,namely, that when the velocity of flow is increased at a given point,the pressure-at the point of increased velocity w1ll decrease andconversely, when the velocity is decreased, as it will be whenthe-cros's-sectional area of the pipe is increased, the pressure at thispoint is invgradually cause water to leak b creased. The projectingflanges 39 serve to i increase the eect which would otherwise bereduced, due to the production of what is cal ed an entrance backpressure'which is present wherever water flows from a larger` pipel intoa smaller pipe. The increased pressure, due to the decrease in thevelocitv and to the entrance head,- is added to the pressure normallypresent in the supply pipe 4 when the water is flowing therein, and thisincreased pressure acts on the piston for opening the valve -13 when thevvalve 25 is opened. As a rule the pressure booster is not necessarybecause the diameter of the piston can be made so large that it willopen and maintain the valve in open position under all circumstances.If, for any reason,'

the water escapes through the groove 32.

As water is incompressible, the piston can move only at a very slow ratewhich may be decreased toward the end of the stroke -by the simpleexpedient of decreasing the cross-sectional area of the channel 32 nearthe topv of the cylinder.

In order to adjust for wear, which will between the sides of the pistonand the cy inder surface, it is only necessary to turn` the screw 33 ina direction to further decrease the cross-sectional area of the openingthrough which the water has to flow to the extent necessary tocompensate for the added leakage,A due to wear.

Cfr

It is evident that if the valve should rev main open the samelength oftime, regard'- less of the pressure of the water in the supply pipe 4,too much water would be used the pressure of the water in the supplypipe and the rate at which the water will flow outwardly through thechannel 32 is directly proportioned to the pressure exerted on thepiston. Therefore the faster the water flows through the valve 13, thefaster the valve will close.

Y pass or channel 32 and the adjustin the dangerof stoppage, due to dirtclogging AThe arrangement of the piston 11, the byscrew 33, shown inFig. 2 and described a ove, is considered satisfactory and takes care ofall dirt found under normal conditions, due to the self-cleaning, wipingaction of the piston past the point ,of screw 33, b ut in order toobviate, to the greatest poss1ble extent,

the channel 32, I have designed an a ternative construction shown inFigs. 4, 5 and 6. In this construction the cap 16, shown in Fig. 2, isreplaced by a cap 161 having a' central tubular member 40 whose lowerend 41 is closed'and provided with a lateral nipple 42 to which theby-pass pipe 43 is connected. rIhis ipe has its other end connected tothe cylmder l() at a point above the highest point reached by the piston111. Secured to the head ofthe piston is a. rod 44 which lits theopening 1n the tubular member 40, which opening is preferablycylindrical and has one side flattened in the manner shown in Figs. 4and 5. A. screw 333 has a threaded connection with the inside of thetubular nipple 45 and has its inner end flattened so that it willcooperate with the ilattened surface of the rod 44. By rotating thescrew 333, the opening between it and the flattenedy side of the rod 44can be adjusted at will. As the rod 44 cannot rotate, due to the actionof the screw and the flattened side, and as the piston '111 is free torotate, it is evident that the rod 44 must be -attached to the piston"by` means which permit relative rotation. I have therefore provided theupper end of the rod 44 with an enlarged head 46 which fits into acavity in the head or' the iston and is held in pla-ce by a suitablepliite 47. The valve casing 2O is connected to the cap 161 and controlsthe water under pressure that opens the valve by raising piston 111.When water is admitted to the cylinder bclow the lower surface of thepiston, the latter naturally moves upward as long as the valve 25 isheld in open position until it has reached the limit of its upwardtravel. lVhen. valve 25 is closed the water in the lower end of thecylinder has no way of escape, except through the tubular member 40 andthe pipe 43 and therefore the piston 111 can move downward only as fastas the water escapes through 40, 42 and 43 to the upper end of thecylinder and the rate of escapo through this passage can be controlledby means of the screw 333 in the mannerA explained. Since the rod 44rcciprocates as the piston'reciprocated in the cylinder, it will alwayskeep the opening clean.

When the pressure is sufficient and the house has a sulliciently largesupply pipe, which should be at least a one inch pipe, the valve can beinstalled in the manner shown and described above, but where theltheupper end of the tank, all in a manner that is broadly old and which-will be hereinafter described more in detail.

It .has been` found that where pressure flow booster tanks of thegeneral type referred to have been installed, difficulty has invariablybeen experienced, due to the fact that the air in the tank '.vill begradually absorbed bythe water and that after some time the air supplytherein will fall below that which is necessary for successfuloperation. When the air supply becomes too low, it-is necessary todisconnect the piping or take other means for replenishing the airsupply.

In order to overcome the difficulty referred to above, I haveconstructed my tank in such a manner that any absorbed air will beseparated from the water as the latter leaves the tank. There are twowell known ways of separating absorbed air from water. @ne is to heatthe water and the other is to decrease the pressure. It is., of course,not practical to heat the water that is used for ushing a toilet andtherefore this method may be disregarded. Where a pressure ilowincreasing tank is employed, the pressure is e ilow booster tankcomprises a decreased whenever the toilet is flushed and therefore -alarge amount of the absorbed air is automatically released at the timethat the lushometer is operative. Although the periodic reduction of thepressure liberates a large .amount of the absorbed air when the water.from the mainfis normally well charged with air, yet when the water fromthe main is deficient in air content, then enough air is retained by theWater to gradua'lly deplete the supplyr inthe tank. I

have found that if I impart to the water in the tank a rotary motion atits time of leaving, when the decrease of pressure liberates a part ofthe absorbed air, then the centrifugal forces will throw these minutebubbles l of liberated air to the center and out of the water and intothe top of the tank where the air is needed. I have therefore arrangedthe supply pipe from the mains in such a manner that the water lwillenter the tank in a tangential direction. This will cause the water torotate and the centrifugal action will operate to move the air towards ll ment.

the centerof rotation where the minute -air bubbles will coalesce andform lar ei-.bubbles which will-rise to the surface an join with the airin the tank. By this simple'expedient, I have' obtained results that area great improvement over the l supply pipes to `the fixtureA 3; The pipe51 connects the tank 50'With the water supply and-'may be of any size.lThis pipe has its end secured to the side of thel tank in, the f mannershown most lclearly inQFig. 104 so that the water when it en terswill-be given a rotary motionfin the direction of the` ar:

in which the flushometer is closed and the piping, including theflow/booster pressurel tank 50, are emplty and then turn. the water intothe same t rough the supply pipe 51,

f the water will iiow into the tank 50-and as it cannot leave'throughthepipe 4, it willl compress the air above the surface of the water untilthe 'air pressure becomes equal to the water' pressure whenv furtherflow of water will cease. The pi e 4 should be at vleast a one inch pipean in the tank 50, im lled b the therefore where the lushometer valve iso-pened the water iorce of the compressed air, wi 1 rush t rough thepipe/1 at a rate corresponding to the lpressure of the air, regardlessof the capacity of the supply pipe 51. As the water leaves through thepipe 4, the pressure on the inside of the 4 tank will decrease and thispermits water to enter through pipe 51 with thevresult that the water inthey tank will be caused to ro- Although'- the rotary motion impartedAto the water assistsl reatly in the liberation tate, as aboveexplained, and this concentrates the air and causes it to become separated from the water.

of absorbed. air'an4 will maintain the air supply when the Water fromthe main is adequately charged .with air, yetin cities f where the wateris inadequate in air content,

some of the air will invariably be carried away from the inside of thetank, with the,

result that thereinainder will, after awhile, y become too small inamount to properly operate the flushometer". In order to automaticallincrease the volume of gas in the tank, I iave provided the followingmeans:

I provide a carbide generator. consisting of a cup-shaped member 53which is 'adapted to contain a quantity of carbide 54. The cup 53 isprovided about its top with an outwardly extending `lange 551 which isladapted to be secured to a corresponding flange of the cap member 56 bymeans of bolts 57. A pipe 58 is connected to the tank 50 at a pointsufficiently near the top to be above the liquid level when thenorordinary arrange- --water down belowthe i ized canvas.

mal quantity of air or gas v"is compressed to the pressure of the watersupply.v Pipe 58- connects with and projects-into the acety` 'of thevacetylene generator with the `top of l the tank 50. This pipe has a'valve 61 which,

.together withfvalve 59,-- serve to close thel H pipes whenever thecarbide supplyris lto be renewed.- 'It 'is evident that whenever thewaterlevel extendsabove the level of pipe 58 thatwater will/'enter thispipe and 'flow through the same and comein contact with @the carbide.Acet`ylene gas `will then be u, generated and this will ow into the tankrows 52. Ifwegassume a condition to exist until the volume ofthe paswill forcethe evel of pipe "58. The valve 59 should be so adjustedthat'the ywater will only enter the generator drop `by drop orat leastvery slowly 'so tha'tthe generation of gas `will not become'excessive.Gaswill be generated for some time after the water has been forced downbelow the level .of the pipe 58 and this will v.cause f the level of thewaterto be movedv down wardly 'to such an extent that it willstake sometime forl the water to absorb a sufficient amount of air or gas to againlenableI it to enter the pipe 58. l By the arrangement just described,it is evident that the gaseous medium in the tank 50 will always beautomatically re plenished whenever the occasion requires.

The above described automatic gas re plenishing means is notl absolutelynecessary where the wateris iven a rotary motion inl the manner descriliprevent the airfrom being depleted for a very long time, when the supplwater is deficient in air content, but cani) may be 'smaller than -tank50 and the air,

instead of being in contact with the inside of the tank and withthewater, is contained in an :ui-:tight bag 65 which may be made 4ofrubber likethe inner tube of an automobile tire, orit may be made ofrubber- The bag 65 is of such size that-'it vfills the tank 64 and isseparated from the sides about the opening 66 by means of a foyraminatedplate 67. Air is admitted into ed, 'as .this valone will I e applied-vin addition whenever the conditions require be under considerableinitial pressure, it

,is evident that the tank'can be much smaller l than tank Afor. thereason that'itA is onl Inecessary that theairv be compressed in' vo,-`

ume to Vthcacfxte'nt l'offthe volumetric 'quanf` tity of j waterrequired flush I .the toilet fixture. As the pressureofthe air on; theinside of the bagii's the-same as' ,the pressure ofthe, water on theoutside,- it Y is evif dent that therelis no tendency. for the air toflow out, except during the short-interval of time during which the tankis emptymg.

Since the bag is-ke t cool by the water and is protectedfrom t e li htand the dry-v in action of the air, it wil last almost 1n. .d

Instead `of 'a tank .likei thatl shown f.'

Fig. 11,-I` may utilize onemade like that shownin cross-section in Fi12. In this modification the tank is ma e of two substantiall identicalmembers 69 and 70, each` with flanges 71 between which aj provide rubberdiaphragm or a loose fitting rubber'- ized canvas bag l72 is'clamped bymeans of bolts 73. "-A valve stem 74 permits air to, be pumped into thespace between the mem; if ber 69 and the diaphragm 72. untilA the latterassumes the dotted line position. Thel pressure of the airand the sizeof the'parts should be such that when the airpressure has reached that'ofthe water supply, then the diaphragm shall have been displaced.. tosuch an extent that the water between it.V 7 0 'is .suliicient to.'

and the side of member flush the toilet. i

In Fi 13 I have show'nan arrangement which differs from that of Fig. `12merely in this, that the rubber diaphragm 72 is re-v placed by acorrugated metal iaphragm 75 made 'in the manner `common .in 4aneroidbarometers. When either oneof the modifications shown in Figs. 11,-12andz13 are used, .the air does not come into contact with loss by'absorption.-

the water and consequently there'icanbe-no When 1t 1s desired that theillpiston.-'tshall' .I

move to normal or closed' v ve position fat ra variable-rate of speed,thesurface ofv the rod 44, which cooperates vviththe end space atdifferent pointsof the stroke. i

Although' attention has previously been called to the fact that -therearel three separate forces acting to close the valve when it has beenopened, I wish to emphasize this feature of the construction, as 1t isexceed.

ingly important. The valve 13 is located on the supply side of the seatand conse-- ressure of uently is acted upon by the p t e water; then thefriction of t e water as itiows by the .valve and its momentum act# ingupon 4the top of theA iston, whilelast but notleast, the weight o thepiston tends to close the'valve. j he valve actssimilar to that of anordinary check-valve and re-l qures no pressure on 'the piston to holdthe valve closed.' Thisl avoids pressure on the piston and preventsleaks` By (puttin the valve 13 onthe pressure side, o not ave any needofpressure on'the iston and this Iprevents any tendency'to lea s.I'consider that the '.arrangementof valve and cylinder.l

- in which the valveis on the pressure side off' i' the valve seat andin'which the three forces,

vtend to close the valve my construction and forms a part pointedoutabove'," 1s new 1 n of my ln'ventionp.

ometer that is ofl simple and su stantialconstruction and'which can bereadily attached toexistin toilet fxtureswithout alteration 1 From .theabove descriptitui,A it is evident'v .that I have produced ,an im rovedflush-v 4as Lthereof. have also produced a combinabeemployed evenwhenethe capacity of the tion of meanswhereby -theflushometer can. no

supply is insuicient to `suppl the necessary v amount of water.v I have'a pressure booster tank provided whereby airwill not -be .absorbedwaterA and Acarried away, and which c'oo crates with the broadcombination to t e extent that itprevents the same from becominginoperative," air inthe tank.

Having now described Iclaim as new isfl- 1. A liushometer comprisin berformed in the sha of a having two axially a' 1 v third openingcommumcating with the firstdue to the depletion oi mentioned-openings,aconical valve seat inA one of said ahgned'g openings, avalve mem'- bercooperative-ly 'e'lated to the valve seat,

the openinglhavingthevalvev 'seat being adapted to ave the Water supplypipe connected thereto', a cylinder connected tothe body member, aipiston; in said cylinder," f. the piston .andi the valve member, a'cyliner head se- 135 the supplyside of the valve, a normall closed of thescrew to delimt the area ofthe open-l Va ing throughl which the waterpasses, can be curved so as to enlarge or diminish the v. means foroperatively connectin cured to said cylinder, a pipe connecting theAspace between the end of the piston wit my invention, what a body'mem-i; said member gned openings, and a l vein said pipe, said cylinderwal havingv a groove on its innersurface and a screw 2. A flushometercomprising, in combination, a valve, means for opening and closing saidvalve, said means comprisin .a cylinder, -a piston slidably mountedvtherein, means comprising a rod for connectiner the .piston to thevalve, said chamber having a groove on its inner surface for forming apassage connecting spaces at opposite ends of the piston, and means forcontrolling the electve area of said passage, said means comprising ascrew operatively related to said groove and adapted to control theeffective cross-sectional area of said passage.

3. A iushometer comprising, in combination, a valve, mea-ns for openingand closing lsaid valve, said "means comprising a cylinder, a pistonslida'bly mounted therein, means comprising a rodI for connectingthepiston to the valve, said chamber having a groove on its inner surfacefor/ forming a passage connecting spaces at opposite ends,I of thepiston, and means forcontrolling the effective area of said passage,said means comprising a. screw operatively related to said groove andada ted to control the efective cross-sectiona area of saidl passage,

and a piston eingmovable past-the end of the screw, whereby a cleaningaction is obtaine .y f v Y In testimony whereof Iat'xx my signature.

' l lIPIYVARD F. HUDSON.

ortion of the outer surface of the l

